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arXiv · 1406.0235

Indications of the topological transport by the universal conductance fluctuations in the Bi2Te2Se microflakes

Zhaoguo Li·Yuze Meng·Jian Pan·Taishi Chen·Xiaochen Hong·Shiyan Li·Xuefeng Wang·Fengqi Song·Baigeng Wang
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Abstract

Universal conductance fluctuations (UCFs) are extracted in the magnetoresistance responses in the bulk-insulating Bi2Te2Se microflakes. Its two-dimensional character is demonstrated by the field-tilting magnetoresistance measurements. Its origin from the surface electrons is determined by the fact that the UCF amplitudes keep unchanged while applying an in-plane field to suppress the coherence of bulk electrons. After considering the ensemble average in a batch of micrometer-sized samples, the intrinsic UCF magnitudes of over 0.37 e2/h is obtained. This agrees with the theoretical prediction on topological surface states. All the evidence point to the successful observation of the UCF of topological surface states.

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Zhaoguo Li, Yuze Meng, Jian Pan, Taishi Chen, Xiaochen Hong, Shiyan Li, Xuefeng Wang, Fengqi Song, Baigeng Wang. 2014-06-02. Indications of the topological transport by the universal conductance fluctuations in the Bi2Te2Se microflakes. https://doi.org/10.7567/apex.7.065202

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